4o 



HARDWICKE'S SCIENCE-GOSSIP. 



Pith Mass Triangular. 



Name and Character of Medullary 

 Rays. 



Betula alba, 4 years old. — 

 Thin, nearly equidistant, 

 radiating in bundles from 

 rounded angles of pith. 



Alnus glutinosus, 4 years old. — 

 Thin, radiating in curvilinear 

 bundles from rounded angles 

 of pith. 



Fagus sylvatica, 8 years old. — 

 5 or 6 broad rays proceeding 

 Irom each side of the trian- 

 gular pith, and widening 

 outwards. 



/ r accinium myrtillus. — Crowd- 

 ed, a few here and there, 

 thickened. 



Character of Ducts or Air-vessels. 



Equally distributed, many 

 compound. 



As above, but smaller. 



Large, abundant, equally dis- 

 tributed in zones. 



Very small, 

 dant. 



Proportion 

 of Pith Area 



to that of 



Wood minus 



Bark. 



I to III 



i to 127 



scattered, abun- 1 1 to 15 



Other Particulars. 



Liber in a complete ring, pith 

 with incurved sides. 



I to 81 Woody tissue, rather coarser 

 than that of Bclula alba. 



Liber abundant in dense par- 

 cels. 



One angle of pith truncated so 

 as to give it a quadrangular 

 aspect. Liber none, or incon- 

 spicuous. 



Platanus orientalis, 2 years old. 

 — Thick and wide apart, wi 1 h. 

 occasional intermediate thin 

 ones. 



Ilex aquifolium, 2 years old. — 

 Some thick, and wide apart, 

 with intermediate thinner 

 ones. 



Acer campestre, 3 years old. — 

 For the most part rather 

 thick, and well defined. 6 

 well-marked clusters. 



Pr units communis, 5 years old. 

 — Straight and nearly equi- 

 distant, of unequal thickness 

 and somewhat flexuose. 



Rhus typhina, 2 years old. — 

 Regular, well defined, dis- 

 tant. 



Acer pseudo-platan us, 3 years 

 old. — Unequally distant, 

 strongly marked, rather 

 thick. 



Fra vinits excelsior, 3 years old. 

 — Thin, evenly arranged, 

 distant. 



Tilia Europcca, 3 years old. — 

 Thin, evenly disposed. 



Pith Mass Ovoid. 



Large, crowded, openings 

 angular. 



Very small and sparse, many 

 compound. 



In rings or bands, moderate 

 in size, many compound. 



Form conspicuous rings in the 

 lines of annual growth, 

 others scattered. 



Large, heaped near lines of 

 annual growth, others few 

 and scattered. 



Of medium size, not very 

 abundant, mostly com- 

 jjound. 



Large, forming conspicuous 

 rings in the lines of annual 

 growth. 



Numerous, varying in size, 

 compound. 



1 to 6 T < D 



1 to 9 



1 to 15 



1 to 55 



r to iv 



I to 5 



to 4fD 



1 to 55 



Edge of woody tissue next pith 

 crenate. Liber in irregular 

 parcels. 



Bark full of crystals. Liber in a 

 thin ring, pith cells full of 

 granules. 



Liber in distinct rings, parcels 

 of external corky tissue, edge 

 near pith crenate. 



Liber in detached parcels wide- 

 ly separate. 



Edge of woody tissue next pith 

 crenate. Liber in curvilinear 

 parcels all round, with a 

 long elliptical opening in 

 each parcel. 



Edge of woody tissue next pith, 

 crenate. Liber in a single 

 ring. 



Liber abundant in concentric 

 circles." 



Liber in wedge-shaped bundles, 

 broad next the woody tissue, 

 narrowing outwards, crystals 

 abundant in the bark. 



Pith Mass Pentangular or Hexangular. 



Salix viminalis, 2 years old. — 

 Regular, rather distant, 

 crowded at angles of pith 

 mass. 



Sul ix alba, 4 years old. — 

 Regular, thin, waved. 



Viburnum lantana, 4 years old. 

 Evenly arranged, and of 

 equal thickness. 



Scattered. 



Scattered, numerous, many 

 compound. 



Of varying size, equally dis- 

 tributed. 



1 to 24 Liber abundant in parcels, pith 

 5-sided. 



1 to 145 Liber in detached parcels, not 

 so abundant as in S. vimi- 

 ualis. 



1 to 19 Liber sparse, bark full of cry- 

 stals. 



